6-(Perfluoroalkyl)uracil compounds are useful as herbicidal agents and methods for their preparation are known in the art. 6-(Perfluoroalkyl)uracil compounds may be prepared by reacting 2-(N,N-disubstituted)amino-4-(perfluoroalkyl)-1,3-oxazin-6-one compounds with amine compounds.
Bull. Soc. Chem. Belg., 101(4), pages 313-321 (1992) discloses that 2-(N,N-dialkyl)amino-4-(trifluoromethyl)-1,3-oxazin-6-one compounds are prepared by reacting ethyl 3-amino-4,4,4-trifluorocrotonate with phosgene iminium chloride compounds. However, this method is not entirely satisfactory because the required phosgene iminium chloride compounds are difficult to handle and relatively expensive. Accordingly, a need exists in the art for an improved process for the preparation of 6-(perfluoro-alkyl)uracil compounds which avoids the use of 2-(N,N-disubstituted)amino-4-(perfluoroalkyl)-1,3-oxazin-6-one compounds.
It is, therefore, an object of the present invention to provide an improved process for the preparation of 6-(perfluoroalkyl)uracil compounds which avoids the use of 2-(N,N-disubstituted)amino-4-(perfluoroalkyl)-1,3-oxazin-6-one compounds.
Other objects and advantages of the present invention will be apparent to those skilled in the art from the description below and the appended claims.